Since 2003, the Language Loggers have been looking at what people say about passives: what people identify as “passive” or “passive voice” (or, sometimes, alas, “passive tense”) and what as not; what they advise about the use of this syntax; and so on.
From the very first posting on passives, the Loggers have noted the inclination of a great many people to identify as passive voice any clause that is “vague on agency” (by failing to assign responsibility for some situation to a specific human agent). (Sometimes it’s clauses denoting situations that are not activities that are so identified.) The agency tradition continues, in two postings today, from Geoff Pullum and Mark Liberman, on Charles Krauthammer, here and here.
Concerns about agency and activity have led a surprising number of people (including many who really should know better) to identify as passive all clauses with the head verb be and to condemn such clauses as “weak”, “inactive”, “vague”, “boring”, and the like. But this fails in both directions: there are passive expressions that lack be and expressions with be that aren’t passive.
Geoff Pullum has assembled an inventory of Language Log postings, available here. (Among these is a fairly long posting of mine about the properties of passives and related phenomena.) Before the inventory, there’s an entertaining little essay about “misdirected grammar advice”, illustrated by a page “from a student paper as corrected in red by a teaching assistant at a top private university on the East Coast of the USA” — showing the “passive = be” idea in its starkest form.
The page has ten P.V. (for “passive voice”) marks on it, but only three of them are correctly identified. In fact, every expression marked this way has a form of be in it, and only one form of be on the page escaped red-penciling (probably by accident), but all except three of the marked expressions are copular be (in combination with a predicative) or progressive be (in combination with an -ing-form verb). Stunning.
In the other direction, the instructor missed an actual passive expression — because there was no form of be in it. That was
[Pope] Innocent saw his people taken from him.
and it is similar in form to an example I recently analyzed on Language Log:
Kansas hasn’t had anyone executed since 1965.
(I’ve taken no position here on whether the underlined material makes a constituent.) Both the Innocent and the Kansas sentences, as wholes, are active, but they contain a passive part: at least a passive VP (taken from him, executed), the subject for which is provided by the preceding NP (his people, anyone). So there are all the ingredients of a passive clause, except a form of the auxiliary be. The Innocent sentence in the original even has a specification of the agent, as the object of the preposition by:
(saw) his people taken from him by the Waldensian heresy and the Albigensian, or Cathar, heresy
(Granted, the agent isn’t human, but it’s still an agent. There are plenty of non-human agents in English.)
This is just one type of be-less passive expressions in English. There are also “get-passives” like
Kim got attacked by bears.
(get here is a main verb, not an auxiliary verb like be). And postnominal modifiers like
Anyone attacked by bears should try not to panic.
And subjectless predicational adjuncts:
Attacked by bears, Kim was terrified.
When attacked by bears, you should try not to panic.
(Note the agent phrases in these examples.)